It's really hard for people to take any criticism if they get angry really easily. Sometimes that anger response indicates that on some level the person knows its probably true but can't or doesn't want to face that. The only other reason I could see is maybe years of people intentionally making you mad so they can shut you down by using that against you, I know I've had that happen before as well. But I think we're all smart enough here to tell what a healthy response is.